The pivoting of timepiece wheel sets has a crucial effect on the quality of the movements. It is expensive to produce pivots, in terms of the number and cost of components and the machining costs of high precision geometric implementations, and the assembly of jewels and shock absorber devices requires particular care.
Conventionally, a pivot for the pivotal guiding of the end of an arbor includes a cabochon housed in a bore or counterbore of the plate, the cabochon containing, housed together in a jewel-setting, a radial guide jewel for the arbor and a support endstone for the axial end of the arbor, and at least one shock absorber device such as a suspension ring for the jewels or jewel-setting. The need for lubrication requires the presence of an oil-pot whose shape must ensure lubrication in any position.
CH Patent No 700496B1 in the name of PATEK PHILIPPE discloses a shock absorber bearing with an elastic means acting axially on a jewel hole comprising a hole for receiving a pivot, and a guide means, which is formed by said elastic means, to force the jewel hole to move only axially, against elastic return means.
EP Patent Application No 2015147A2 in the name of ULYSSE NARDIN discloses a shock absorber bearing including a pivoting member with at least one resilient arm and a central portion including a hole for receiving a pivot, which are formed in a single-piece in a disc of single crystal material.
WO Patent Application No 20111161139A1 in the name of SWATCH GROUP R&D discloses a shock absorber bearing for a wheel set arbor including a pivot-shank extended by a pivot, comprising a support provided with a housing arranged for receiving a suspended pivot system into which the pivot-shank is inserted. The pivot system absorbs any shocks that the wheel set undergoes and is formed in a single-piece made of an at least partially amorphous metal alloy. EP Patent Application No 2400355A1 in the name of SWATCH GROUP R&D also discloses a bearing fulfilling the same function which includes elastic means, arranged to exert at least an axial force on the pivot system, and made of an at least partially amorphous material.
EP Patent Application No 2607971A1 in the name of SWATCH GROUP R&D discloses a method of producing a bearing including a recess, in a substrate, wherein the structure of one area of the substrate is modified in order to make it more selective, wherein this area is chemically etched to produce the bearing, wherein the substrate is made of laser wavelength transparent material, wherein at least one recess is used to form a resilient structure, which includes a central part arranged so that the pivot-shank of an arbor can be inserted therein and at least one resilient arm extending from said central part.